Natural Pasta-Filata Style Cheese With Improved Texture

ABSTRACT

A natural pasta filata style cheese with improved textural attributes achieved by altering various natural cheesemaking parameters.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.17/178,660 filed Feb. 18, 2021, which is hereby incorporated byreference.

FILED OF THE INVENTION

The present disclosure relates to the manufacture of a natural pastafilata style cheese and, more specifically, to the manufacture of anatural pasta filata style cheese having improved textural attributes.

BACKGROUND OF THE INVENTION

Pasta filata style cheese loses its fibrous texture over time. Initiallyafter manufacture, 50% of the total moisture in such cheese can beexpressed using centrifugation. During refrigerated storage, theexpressible moisture declines such that after approximately 30 days,such cheese has no expressible moisture. This can be explained by thechange in microstructure of the cheese. Initially, the protein strandsthat are the basis for fiber formation are separated by channelscontaining fat and moisture. The moisture in the channel is graduallyabsorbed by the protein matrix to the extent it is no longer easilyexpressed and the fat globules are completely encased by the proteinmatrix. During refrigerated storage, proteolytic enzymes such as fromany residual coagulant and the starter culture act to breakdown theproteins in the cheese. As the amount of intact protein decreases duringstorage, this weakens the crosslinks between individual proteins thatmake up the cheese protein matrix and increases the tendency for theproteins to be associated with moisture rather than with each other.

SUMMARY OF THE INVENTION

In one construction, the disclosure provides a method for making anatural string cheese that has expressible serum 30 days aftermanufacture and refrigerated storage comprising the steps of using milkwith at least 4% milk protein, adding calcium prior to renneting,ripening at a temperature of at least 95° F. and stretching at atemperature of at least 130° F. and a pH of at least 5.25.

Other aspects of the disclosure will become apparent by consideration ofthe detailed description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flowchart of a method to manufacture a natural pasta filatastyle cheese.

FIG. 2 is a flowchart of second embodiment of a method to manufacture anatural pasta filata style cheese.

FIG. 3 is a flowchart of a third embodiment of a method to manufacture anatural pasta filata style cheese.

DETAILED DESCRIPTION OF THE INVENTION

Before any embodiments of the disclosure are explained in detail, it isto be understood that the disclosure is not limited in its applicationto the details of construction and the arrangement of steps set forth inthe following description or illustrated in the following drawings. Thedisclosure is capable of other constructions and of being practiced orof being carried out in various ways.

The cheesemaking methods described herein provide a pasta filata stylecheese with improved textural attributes that are achieved by alteringvarious natural cheesemaking parameters. For example, the fibroustexture or stringiness of the cheese produced is maintained for longerperiods of time and the amount of retained serum or juiciness ismaintained for longer periods of time, both as compared toconventionally produced cheese. Those longer periods of time includeafter 30 days, 50 days, 80 days, 100 days, or 120 days, for example.

With reference to the cheesemaking method of FIG. 1 , this methodincludes the addition of calcium after stretching. The calcium is addedat a level of between 0.2%-2.0% and, more specifically, in the range of0.6%-2.0%, and in the range of 0.6%-1.0%.

This method results in a cheese with higher expressible moisture orserum over a period of time such as at 30 days as compared toconventionally produced cheese where there is generally no measurableexpressible serum after 30 days. The amount of serum that can beexpressed by centrifuge from the cheese can be tested as is known in theart. The addition of calcium after stretching approximately doubles thelength of time in which the juiciness of the cheese is retained ascompared to string cheese manufactured without adding calcium beforeextruding. Cheese so treated with calcium lose their stringiness slowerover time and expressible serum at 30 days and 50 days, for example.

To demonstrate changes in textural attributes over time, other texturalanalysis can be conducted such as hardness, springiness, resilience,cohesiveness, adhesiveness, and chewiness, as is known by those of skillin the art. Such textural analysis demonstrates that the cheese producedin the method of FIG. 1 has improved textural characteristics over aperiod of time as compared to conventionally produced string cheese. Theextent of textural characteristic changes, such as stringiness of thecheese, can be observed visually over time.

The microstructure of the cheese produced from the method of FIG. 1 isaltered as compared to conventionally produced string cheese which canbe demonstrated using samples fixed in glutaraldehyde/formaldehyde andimaged using transmission electron microscopy, with the samples embeddedin resin, sectioned to approximately 200 nm in thickness and stainedwith heavy metals, for example. The microstructure of the cheeseproduced from the method of FIG. 1 (i) has wider fat-serum channels thatprovide more easily propagated fractures, (ii) has a reduced tendencyfor the protein matrix to become more hydrated by increasing theprotein-protein interactions, (iii) takes longer for the serum aroundthe fat droplets to be absorbed into the protein matrix, (iv) takeslonger for the protein matrix to expand and encase the fat globules, (v)has the serum-fat channels remain as separate entities with a thin layerof serum between the fat globules and the protein matrix and (vi) has anincreased amount of small serum spaces scattered throughout the proteinmatrix. The serum-fat channels allow the protein matrix to be pulledapart at these channels and allow for that breakage to be propagatedalong these channels, thus allowing strings of cheese to be pulled.

One example process of the method of FIG. 1 to produce string cheese isas follows. It should be noted that other natural pasta filata stylecheese can also be manufactured using the illustrated process and thespecific parameters and components set forth below can be altered. Lowmoisture part skim mozzarella cheese curd is manufactured frompasteurized milk standardized to 2% milkfat, from a Streptococcusbacteria such as Streptococcus thermophilus starter culture and from alow proteolytic rennet enzyme such as camel chymosin, for example. Thecurd is stretched and heated. Calcium, preferably in the form of calciumchloride, is added to the hot cheese in a brine solution aftercooking/stretching but before extrusion. The calcium content is in therange of 0.2-1.0%.

The cheese produced from the method of FIG. 1 has altered texturalcharacteristics and a different microstructure enabling the freshcharacteristic of the string cheese to be maintained over a longerperiod of time thus improving textural attributes.

Turning now to FIG. 2 , a second embodiment of a cheesemaking method toimprove textural attributes of a natural pasta filata style cheese isillustrated. This method includes the addition of calcium afterstretching at a level of between 0.2%-2.0%, more specifically in therange of 0.6%-1.0%, and more specifically 0.6%. The method includes acurd stretching pH in the range of 5.25-5.45 and, more specifically, inthe range of 5.3-5.45. The method includes a curd stretching temperaturein the range of 130-140° F., and more specifically 135° F.

This method results in a cheese with higher expressible moisture over aperiod of time such as at 30 days, 50 days, 80 days, 100 days, or 120days as compared to conventionally produced cheese and with slower losesin stringiness and expressible serum. The extent of serum that can beexpressed by centrifuge from the cheese can be tested as is known in theart. The addition of calcium and the choice of stretching pH andstretching temperature enables the cheese to have expressible serumafter 100 days of refrigerated storage.

To demonstrate changes in textural attributes over time, other texturalanalysis can be conducted such as hardness, springiness, resilience,cohesiveness, adhesiveness, and chewiness as is known by those of skillin the art. Such other textural analysis demonstrates that the cheeseproduced in the method of FIG. 2 loses its stringiness slower over timeas compared to conventionally produced string cheese.

The microstructure of the cheese produced from the method of FIG. 2 isaltered as compared to conventionally produced string cheese which canbe demonstrated using samples fixed in glutaraldehyde/formaldehyde andimaged using transmission electron microscopy, with the samples embeddedin resin, sectioned to approximately 200 nm in thickness and stainedwith heavy metals, for example. The microstructure of the cheeseproduced from the method of FIG. 2 : (i) keeps the fat/serum channelsseparate from the protein matrix so that the channels act as points ofweakness that allow the cheese to be pulled apart, (ii) maintains theprotein matrix as parallel strands that give the cheese increasedspringiness, and (iii) prevents the whole cheese mass from fusingtogether.

One example process of the method of FIG. 2 to produce string cheese isas follows. It should be noted that other natural pasta filata stylecheese can also be manufactured using the illustrated process and thespecific parameters and components set forth below can be altered. Lowmoisture part skim mozzarella cheese curd is manufactured frompasteurized milk standardized to 2% milkfat, a Streptococcus onlystarter culture such as Streptococcus thermophilus and a low proteolyticrennet enzyme such as camel chymosin. After whey draining, when the curdreaches pH 5.4, it is salted with 1%. The curd is placed in acooker/stretcher and heated to between 135° F. and 145° F., in a hot 5%bring solution. Calcium, preferably in the form of calcium chloride, isadded to the hot cheese in the brine solution after cooking/stretchingbut before extrusion.

The cheese produced from the method of FIG. 2 has altered texturalcharacteristics and a different microstructure enabling the freshcharacteristic of the string cheese to be maintained for a longer periodof time thus improving textural attributes.

Turning now to FIG. 3 , a third embodiment of a cheesemaking method toimprove textural attributes of a natural pasta filata style cheese isillustrated. This method includes use of milk with at least 4% milkprotein, addition of calcium prior to renneting, ripening at atemperature of at least 95° F., stretching at a temperature of at least130° F. and stretching at a pH of at least 5.25. The calcium added priorto renneting is greater than 0.01%, and more specifically in the rangeof 0.01-0.02%. The ripening temperature is at least 95° F., and morespecifically, in the range of 95-105° F. The stretching pH is at least5.25, and more specifically, in the range of 5.25-5.45, and moreparticularly 5.45. The stretching temperature is at least 130° F., andmore specifically, in the range of 130-145° F. and more particularly145° F.

The cheese produced by the method of FIG. 3 retains expressible serumthrough at least 100 days of refrigerated storage.

To demonstrate changes in textural attributes over time, other texturalanalysis can be conducted such as hardness, springiness, resilience,cohesiveness, adhesiveness, and chewiness as is known by those of skillin the art. Such other textural analysis demonstrates that the cheeseproduced in the process of FIG. 3 loses its stringiness slower over timeas compared to conventionally produced string cheese. Stringiness wasalso observed visually over time by pulling apart the cheese andobserving the formation of strings.

The microstructure of the cheese produced from the method of FIG. 3 isaltered as compared to conventionally produced string cheese which canbe demonstrated using samples fixed in glutaraldehyde/formaldehyde andimaged using transmission electron microscopy, with the samples embeddedin resin, sectioned to approximately 200 nm in thickness and stainedwith heavy metals, for example. The microstructure of the cheeseproduced from the method of FIG. 3 : (i) keeps the fat/serum channelsseparate from the protein matrix so that the channels act as points ofweakness that allow the cheese to be pulled apart, (ii) maintains theprotein matrix as parallel strands that give the cheese increasedspringiness, and (iii) prevents the whole cheese mass from fusingtogether.

One example process of the method of FIG. 3 to produce string cheese isas follows. It should be noted that other natural pasta filata stylecheese can also be manufactured using the illustrated process and thespecific parameters and components set forth below can be altered. Skimmilk is adjusted by ultra-filtration to about 2× concentration thenadded to whole milk to produce a higher fat milk of at least 4% with aprotein/fat ratio of 1.4, for example. Calcium, preferably in the formof calcium chloride, is added to the milk prior to renneting such asbetween 0.01-0.02%. A starter culture, such as Streptococcusthermophilus, for example, is added. A ripening temperature of 105° F.is utilized. A low proteolytic rennet, such as camel chymosin rennet forexample, is added to the milk at a concentration of 3-10 mL per 1000 lbof milk and coagulated at a temperature of 95° F. The cheese isstretched at a cheese temperature of 145° F. and at a pH of 5.45.Thereafter, the cheese is extruded, brined, and stored.

In this third embodiment, the rate at which protein strands in thecheese become more water-compatible and fuse together so that serum/fatchannels remain between them is slowed. The protein-protein interactionsare increased, protein-water interactions are reduced and proteolysisduring storage is reduced so that protein chains remain intact ratherthan being broken into shorter chainer that interact more readily withwater. With a higher ripening temperature, the amount of rennet can bedecreased by approximately 30-80%, for example. Adding calcium to themilk speeds up coagulation and thus reduces the amount of coagulantneeded. Increasing the protein content of the milk speeds upcoagulation. Increasing the set temperature of the milk speeds upcoagulation.

The cheesemaking methods described herein provide a pasta filata stylecheese with enhanced textural attributes such as stringiness andjuiciness. It should be noted that the sensory characteristics may beaffected by the methods disclosed herein but any changes can be suitablealtered as is needed.

Various features and advantages of the invention are set forth in thefollowing claims.

1-8. (canceled)
 9. A method for making string cheese comprising thesteps: providing milk; adding a starter culture to the milk; addingcalcium to the milk; ripening the milk; adding a rennet enzyme to themilk; coagulating the milk at a coagulation temperature of at least 95°F.; producing curd; stretching the curd at a stretching temperature ofat least 130° F. and a stretching pH of at least 5.25; forming stringcheese from the curd; and storing the string cheese at a refrigeratedtemperature for at least 30 days; wherein the string cheese hasexpressible serum after 30 days.
 10. The method of claim 9 wherein therennet enzyme is a low proteolytic rennet enzyme.
 11. The method ofclaim 9 wherein at least 0.01% by weight of the milk calcium is added tothe milk.
 12. The method of claim 9 wherein 0.01 to 0.02% by weight ofthe milk calcium is added to the milk.
 13. The method of claim 9 whereinthe coagulating temperature is between 95-105° F.
 14. The method ofclaim 9 wherein the stretching temperature is between 130-145° F. 15.The method of claim 9 wherein the stretching pH is between 5.3 and 5.45.16. The method of claim 9 and further including the step of measuringthe expressible serum after 30 days.
 17. A method for making stringcheese comprising the steps: providing milk; adding a starter culture tothe milk; adding calcium to the milk; ripening the milk; adding a rennetenzyme to the milk; coagulating the milk; producing curd; stretching thecurd at a stretching temperature of at least 130° F. and a stretching pHof at least 5.25; forming string cheese from the curd; and storing thestring cheese at a refrigerated temperature for at least 30 days;wherein the string cheese has expressible serum after 30 days.
 18. Themethod of claim 17 wherein the rennet enzyme is a low proteolytic rennetenzyme.
 19. The method of claim 17 wherein at least 0.01% by weight ofthe milk calcium is added to the milk.
 20. The method of claim 17wherein in the coagulating step, coagulating the milk at a coagulationtemperature of between 95-105° F.
 21. The method of claim 17 and furtherincluding the step of measuring the expressible serum after 30 days. 22.A method for making string cheese comprising the steps: providing milk;adding a starter culture to the milk; adding calcium to the milk;ripening the milk; adding a rennet enzyme to the milk; coagulating themilk at a coagulating temperature of at least 95° F.; producing curd;stretching the curd; forming string cheese from the curd; and storingthe string cheese at a refrigerated temperature for at least 30 days;wherein the string cheese has expressible serum after 30 days.
 23. Themethod of claim 22 wherein the rennet enzyme is a low proteolytic rennetenzyme.
 24. The method of claim 22 wherein at least 0.01% by weight ofthem milk calcium is added to the milk.
 25. The method of claim 22wherein the coagulating temperature is between 95-105° F.
 26. The methodof claim 22 wherein in the stretching step, stretching the curd at astretching temperature of between 130-145° F.
 27. The method of claim 22wherein in the stretching step, stretching the curd at a stretching pHof between 5.3 and 5.45.
 28. The method of claim 22 and furtherincluding the step of measuring the expressible serum after 30 days.